Here is a shot of part of a sculpture I found in a park. I can't decide if I like the composition or not. On one hand, I think the dark stone looks good against the sky, but I think the tree is annoying. Also should I have moved a bit to the left? Let me know any suggestions, since there is something about the composition which doesn't sit right with me, but I can't figure out why!

There is a mass of black in the centre of your photo. No more than that. You even tried to selectively brighten it (it now has a very visible halo, which is not good, I say). It is not immediately recognisable as the sculpture that you have seen as a whole but we, the viewers, don't know. Therefore all we see is that big black mass ... and big black masses are not quite as interesting as you had hoped your photo might be, I guess.